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A convenient electrochemical approach to new redox-active Cu, Pd, Ni -containing polymers of polyamic type with biquinoline (biQ) fragments was elaborated. The comparative analysis of the data obtained revealed the main factors which influence the type of metal coordination unit formed in the polymer: the nature of metal, the number of biQ fragments and conformational rigidity of the polymer backbone as well as the electrolysis conditions. Voltammetric investigation of metal-polymers allows distinguishing the types and relative amounts of metal-coordination units formed. The comparison of the electrochemical data with the results of catalytic tests revealed the guidelines for electrochemical synthesis of efficient catalytic systems.

Phthalocyanine and naphthalocyanine complexes with redox-inactive metals adsorbed on activated carbon supports were shown to be effective catalysts for CO 2 electroreduction in the form of gas diffusion electrodes, yielding carbon monoxide with current efficiencies up to ca. 75%. A mechanism for CO 2 electroreduction catalyzed by these complexes has been proposed in which the key step is the coordination of a CO 2 molecule to the external N-atom of the phthalocyanine or naphthalocyanine ring.

Porphyrin and phthalocyanine transition metal complexes adsorbed on activated carbon fiber nanoporous supports are shown to be effective catalysts for CO 2 electroreduction in the form of gas diffusion electrodes, yielding carbon monoxide with current efficiencies up to ca. 70%. A comparison of the efficiency of activated carbon supports with a wide pore size distribution, and activated carbon fibers, with slit-shaped pores of ca. 2 nm width, demonstrates that an increase in the catalyst dimensions results in a decrease in the benefit of the so-called nanospace effect. For bulky molecules, e.g., tetra-tert-butyl-substituted phthalocyanines, activated carbon supports are more effective, with a current efficiency as high as 85% for CO production being achieved.